FIG. 1 is an exploded perspective view showing a prior art vacuum cleaner. The vacuum cleaner comprises a cleaner body 1 that encloses therein, a motor for driving a fan that generates a suction force. The vacuum cleaner also includes an extension hose 10 connected to the cleaner body 1, and a suction brush assembly 20 connected to the extension hose 10 through which dust on a surface being cleaned is drawn.
The extension hose 10 comprises an extension pipe 14 and an extension pipe connecter 12. A first end of the extension pipe connector 12 is connected to the suction brush assembly 20; the opposite end of the extension pipe connector 12 is connected to an extension pipe 14 that is in turn connected to a suction hose 16. One end of the suction hose 16 is connected to the extension pipe 14; the opposite end of the suction hose 16 is connected to the cleaner body 1.
With the arrangement shown in FIG. 1, dust can be drawn in through the suction brush assembly 20, passed through the extension pipe connecter 12, the extension pipe 14 and the suction hose 16 and finally into the cleaner body 1 where it is collected in a dust collecting chamber (not shown).
The suction brush assembly 20 comprises a cover 22, an assembly body 30 connected to which the cover 22 is attached. The assembly body 30 has a suction inlet 36 at a bottom surface thereof. The assembly body 30 also includes a turbine fan 90 rotatably mounted to the assembly body 30 between two axes 90 and two screw or “worm” drives 72, each of which is operatively coupled to a corresponding worm gear 74.
A rotation body 80 mounts a cleaning member 82 such as a dust cloth at a lower part thereof. The rotation body 80 is rotatably mounted on a rotation body mounting boss 40 of a rotation body receiving space 38 formed on the assembly body 30.
When the motor (not shown) in the cleaner body 1 operates, a suction force is generated at the suction inlet 36 at the bottom of the assembly body 30, thereby drawing in dust-laden air from a surface being cleaned. The drawn-in air collides with a turbine blade 92 provided to the turbine fan 90, thereby causing the turbine fan 90 to rotate. When the turbine fan 90 rotates, the worm drive 72 coaxially formed with the turbine fan 90 is rotated. Since the worm drive 72 is engaged with the worm gear 74, rotation of the worm drive 72 by the turbine fan 90 causes the worm gear 74 to rotate. The driving force transmitted to the worm gear 74 rotates the rotation body 80, thereby causing the cleaning member 82 mounted at a lower part of the rotation body 80 to rotate. Rotation of the cleaning member 82 facilitates dust collection from a surface being cleaned (not shown).
As shown in FIG. 2, as the rotation body 80 of the cleaning member 82 rotates over a surface, dust on the surface tends to be drawn in to the relatively narrow space 200 between a bottom plate 39 of the rotation body receiving space 38 (FIG. 1) and a cleaning member mounting part 84 of the rotation body 80. Drawn-in dust then tends to accumulate between the even narrower space between the rotation body 80 and the rotation body mounting boss 40. Dust also flows into the rotation body receiving space 38 and tends to accumulate on and near the worm drive 72 (FIG. 1) and the worm gear 74 (FIG. 1). Because of dust that accumulates over time, the rotation body 80 begins to be impeded by the accumulated dust. Over time, the cleaning member's rotation body 80 loses its effectiveness and cleaning effectiveness deteriorates.
Moreover, since the distance between the suction inlet 36 and the turbine fan 90 is short, as shown in FIG. 3, noise generated from the turbine fan 90 and other component parts is emitted to the outside of the suction brush assembly 20 through the suction inlet 36. The noise, especially of high frequency region, may be offensive to a user. Thus, there is exists a need for a vacuum cleaner suction brush assembly having a rotating cleaning element or member that is less susceptible to dust accumulation and which reduces noise generation. There also exists a need for a vacuum cleaner having such a suction brush assembly.